164 



MISSOURI BOTANICAL GARDEN. 



Erccldites hicracijolia, Aster azureus, A. cordijolius and A. 

 turbinellus, Eupatorium ageratoides, Solidago radula, S. rigida 

 and S. spedosa. From July or August on Vernonia nov- 

 cboraccnsis, occurring in clumps, has been in full bloom. At 

 this time too, the Labiatac form an important part of the 

 ground cover, especially Monarda fistulosa, Pycnanthemum 

 muticum pilosum and P. linifolimn. These occur ordinarily 

 in small clumps composed of but a few plants. 



Dry hilltops. 



The oaks occurring here, besides Quercus cocdnea iinctoria, 

 are Q. alba, Q. Muhlenhergii, Q. nigra, Q. stellata and Q. 

 Sdmeckii which, with Carya alba, C. pordna odomta, C. tomen- 



iosa and Sassaf 



>fjidnalc, form the main aspect. The 



trees being farther apart than in the typical oak forest and 

 often even isolated, an opportunity is offered for the growth 

 of numerous species ordinarily not found in the latter forma- 

 tion, including trees, shrubs and herbs. Among the trees is 

 Robinia Pseudacada of which isolated specimens are met 

 with here, as is the case with Prunus serotina which here 

 perhaps reaches its greatest development. . Though of this 

 species a single large tree is sometimes found here, it ordina- 

 rily forms thickets, alone or with Rhamnus caroliniana, Rhus 

 covallina, R. qlahra and Viburnum prunijolium. It is to be 



herbaceous 



bein 



The spring flora is not as characteristic in this location, and 

 consists of Anemonella thalidr aides , Ranunculus fasdcularis 

 and Capsella Bursa-pastoris, together with Viola pedata, which 

 here reaches its highest development and of whic^h sometimes 

 the variety hicolor is found. The rosette character of the 

 spring flora is further emphasized by plants of Erigeron helli- 

 dij alius, Gnaphalium polycephalum, Androsace ocddentalis, 

 Verhascum Thapsus, Verbena Aubletia and Plantago pata- 

 gonica aristata. Specimens of Comandra umhcllata, Sisy- 

 rinchium albidum, S. anceps and Nothoscorduni striatum oc- 

 cur with varying frequcnicy. 



During the summer Helianthus ocddentalis, Rudbeckia 

 hirta, Solidago rigida, Verbedna helianthoides, Lobelia in- 



